C2000™︎ microcontrollers

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TMS320F280049: F280049 oscillator failure when using external crystal

Sheldon He

Expert 8585 points

Part Number: TMS320F280049

Hi expert,

My customer is running digital power projects, in a recent test, they meet oscillator failure issue in their project. We may need your expertise to help identify the cause and fix this problem.

Their F280049’s internal oscillator may stop output when high power is on and this problem is easy to reproduce on many of their models. Different working conditions can cause different distortion on oscillator’s output.

And they have captured waveform as attached.

Could you and your team kindly help us with this?

Thanks

Sheldon

over 6 years ago

0 Frank Ankapong over 6 years ago

TI__Mastermind 28275 points

Hi Sheldon,

Thanks for providing the waveforms and schematic. We will be happy to help.

However, can you clarify what we are looking at in the waveforms? They don't have any annotations. What signals are on the different channels?

Please provide as much information as you can so we can help quickly resolve this.

0 Sheldon He over 6 years ago in reply to Frank Ankapong

TI__Expert 8585 points

Hi Frank,

The blue and yellow are wave captured form X1 and X2 pin, you can ignore the purple one.

Thanks

Sheldon

0 Frank Ankapong over 6 years ago in reply to Sheldon He

TI__Mastermind 28275 points

Hi Sheldon,

It looks like the device is possibly resetting. We need more information on the failure trigger condition.

1. Can you provide more details on what "high power on" is?

2. Are they using external or internal supply for VDD12 rail?

Can you provide scope shot of VDDIO, VDD and XRSn as the failure condition is entered?

0 Sheldon He over 6 years ago in reply to Frank Ankapong

TI__Expert 8585 points

Hi Frank,

I think we get the cause, its from a floating JTAG cable.

Thanks for your help, please close this thread.

Sheldon

0 Frank Ankapong over 6 years ago in reply to Sheldon He

TI__Mastermind 28275 points

Sounds good Sheldon. Glad they figured out what the issue was.